Lloyd's of London, the oldest insurance market in the world, has admitted it needs more money to pay claims resulting from the destruction of New York's World Trade Center on 11 September.

Lloyd's is looking for an extra �501m, or an average of about �33,000 from each of the "Names" or individual investors.

Unlike in former years, the Names are not the primary underwriters of Lloyd's. After the market nearly collapsed in the 1980s and early 1990s, the weight has largely shifted to corporate underwriters.

From 2005 on, names with unlimited liability could be phased out.

But still the cash call is formidable, since the market has already asked for �780m in October last year.

In all, Lloyd's has estimated its total costs from the WTC disaster at �1.9bn.